37 lines
1.5 KiB
C
37 lines
1.5 KiB
C
/* cdb_hash.c: cdb hashing routine
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*
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* This file is a part of tinycdb package.
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* Copyright (C) 2001-2023 Michael Tokarev <mjt+cdb@corpit.ru>
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included
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* in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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* DEALINGS IN THE SOFTWARE.
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*/
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#include "cdb.h"
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unsigned
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cdb_hash(const void *buf, unsigned len)
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{
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register const unsigned char *p = (const unsigned char *)buf;
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register const unsigned char *end = p + len;
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register unsigned hash = 5381; /* start value */
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while (p < end)
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hash = (hash + (hash << 5)) ^ *p++;
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return hash;
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}
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